1. Field of the Invention
The present invention relates to a novel method of industrial, automated manufacture of light gage steel floor, roof and wall panels, with exceptional energy properties, to form stronger building modules of varying width, height and length. The invention provides structures of one to four stories for homes, offices, motels, hotels and other cellular structures. The method also allows aesthetic flexibility for a wide range of products, from traditional family home designs to contemporary structures including large glass surfaced areas and spatial elements. The invention uses lighter weight materials; thereby reducing module weight by approximately 40% of modules produced by the current wood modular industry and significantly reduces shipping costs from the manufacturing plant to the erection site.
2. Description of the Related Art
The intent of the modular industry is to provide a finished, quality housing product in the shortest amount of time. However, the current modular industry has not yet achieved full integration of mechanical and utility services as part of an automated production system and is still reliant upon labor intensive technology, historic materials and outdated modes of structural framing. There is vast improvement possible in all stages of module construction, transport and erection.
In addition to requiring weeks to finish a typical 2,000 ft2 house, the industry wastes time and money with outmoded transport methods. For instance, the major structural elements of modular construction are longitudinal members, which support transverse joists to create the floor panel of the module. The industry usually locates the members in either the field of the panel to allow the transverse joists to cantilever to the outside width dimension of the module or as a frame for floor panels with joists extended to the inside of perimeter wood beams that support the module during crane erection at the site. The second method requires expensive, heavy steel framed multi-axle transport trailers to limit damage to gypsum and other relatively soft interior finishes due to module flexion during transport.
Currently the industry standard is far from the ideal product of a complete module including integrated mechanical and utility services, full insulation and efficient use of materials. Although certain modular industry products approximate the ideal, the mainstream modular industry has developed without the structural, cost and aesthetic advantage of galvanized light gage steel rolled shapes and automated production technologies.
Despite the potential, light gauge steel has not historically been economical primarily due to difficult connection problems. The attachment of light gauge steel shapes to construct panels for modular structures, limited by national codes and conventions that adhere to historic structural configurations and fastening details, fails to take advantage of the inherent strength of light gauge steel materials. The galvanized surface that protects steel from rust and corrosion limits the use of welding attachment due to the toxic gas emitted during the welding process. The use of screw and nailing attachment of the members used to construct onsite structures is labor intensive and does not lend itself to either the multiple directions required of application tools in fastening multiple members or the creation of complex composite structural configurations needed to develop the strength capabilities of light gauge steel rolled shape members.
Recent advances in fastening technology promise an economical solution for jointing of light gauge steel. Press joining of light gage metals was introduced in Europe in the late 1980's, tested and proven, and since, tested and approved by most of the building codes in the United States. The activation of the press joint is fast, inexpensive and provides proven consistent joint strength for light gauge steel. However, the press joining tools, which can provide fastening of light gage galvanized steel sheets, are bulky and do not lend themselves to multi flexible positioning required for complex designs and difficult to reach members of complex composite designs. These problems must be solved before the press joining technology is introduced for automated module fabrication.
The historic structural configurations preferred and included in today's codes are based on labor intensive materials and hand held tools, which do not lend themselves to automation and the use of press joining fastening. Limited by current technology, the modular industry has not advanced beyond outdated models and modes of production. The object of the invention is to incorporate two technologies; light gage galvanized rolled structural shapes and the press joining technology, in an automated module manufacturing system by inventing new structural configurations and procedures which build upon the assets of each technology to create 21st century structures.